Merge pull request #700 from The-Keshav-Agarwal/FibonacciNumber

Added Code For nth Fibonacci Number in c

Author: theyashshahs

fibonacci_number/FibonacciNumber.c

@@ -0,0 +1,43 @@
+#include <stdio.h>
+
+long long int FibonacciNumber(long long int n)
+{
+	//Because first fibonacci number is 0 and second fibonacci number is 1.
+	if (n == 1 || n == 2)
+	{
+		return (n - 1);
+	}
+	else
+	{
+		//store last fibonacci number
+		long long int a = 1;
+		//store second last fibonacci number
+		long long int b = 0;
+		//store current fibonacci number
+		long long int nth_Fib;
+		for (long long int i = 3; i <= n; i++)
+		{
+			nth_Fib = a + b;
+			b = a;
+			a = nth_Fib;
+		}
+		return nth_Fib;
+	}
+}
+
+int main()
+{
+	long long int n;
+	printf("Enter a Number : ");
+	scanf("%lli", &n);
+	if (n < 1)
+	{
+		printf("Number must be greater than 0");
+	}
+	else
+	{
+		long long int nth_Fib = FibonacciNumber(n);
+		printf("Fibonacci Number is %lli", nth_Fib);
+	}
+	return 0;
+}